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Hetzner MCP

Model Context Protocol server for full Hetzner Cloud + Storage API automation

Expose all official Hetzner operations as MCP tools so AI agents can manage servers, networking, load balancers, firewalls, volumes, DNS zones, and storage boxes from one server.

PyPI Python MCP License


Install

pipx install hetzner-mcp
hetzner-mcp install

Then set your token and restart your MCP client:

export HETZNER_TOKEN="your_token_here"

Or configure it once via CLI (persisted local config):

hetzner-mcp auth set --token "your_token_here"

What It Does

hetzner-mcp loads official OpenAPI specs from Hetzner and exposes operations as MCP tools.

  • Full Cloud API coverage: https://api.hetzner.cloud/v1
  • Full Storage API coverage: https://api.hetzner.com/v1
  • Dynamic tool generation from operation IDs
  • Helper tools for discovery, search, and operation schema inspection
  • Action polling helper for async action workflows

Core helper tools

Tool What it does
list_api_operations List all operations with filters (domain/tag/method/query)
search_api_operations Search operations by keyword
get_api_operation_details Inspect full operation details and input schema
list_api_categories List all API categories/tags with docs descriptions
get_api_category_details Explain one category in depth with all endpoints inside
list_api_projects Show configured project profiles and active credential context
set_active_api_project Switch active project profile for agent execution context
wait_for_action Poll cloud/storage actions until completion

All API operations are also exposed directly as tools using the official operation ID names (for example create_server, get_action, create_storage_box).

For agent-friendly documentation, every endpoint and category also has dedicated guide tools:

  • Endpoint guide tool pattern: guide_<operation_id>
    • Example: guide_create_server
  • Category guide tool pattern: category_guide_<api_domain>_<category_slug>
    • Example: category_guide_cloud_servers

These guide tools include docs text from the OpenAPI documentation, explicit purpose, parameter explanations, and example tool arguments.

Docs-first execution lock (required)

This server enforces a docs-first workflow for endpoint execution:

  1. Call guide_<operation_id> first for the endpoint you want to execute.
  2. Then call the endpoint tool itself (for example create_server).

If you skip step 1, execution is rejected with a docs_required error.

Unlocking is based on context freshness (interaction distance in the current session), not wall-clock time:

  • Docs must be read before execution.
  • Recently executed endpoints remain trusted while context is still fresh.
  • After enough unrelated tool interactions (context drift), docs must be read again.

Full Coverage

Current generated operation coverage:

  • Total operations: 221
  • Cloud operations: 189
  • Storage operations: 32

You can verify this locally:

python scripts/verify_operation_coverage.py

Example Prompts

"List all Hetzner operations related to firewalls"
"Create a CX22 server in fsn1-dc14 with my SSH key"
"Attach volume 12345 to server 67890"
"Create a load balancer and add target server 1001"
"Enable rescue mode on server 123 and wait for action completion"
"Create a storage box and reset its password"
"Show operation details for update_storage_box_access_settings"

Authentication

You can configure auth in two ways:

  1. Environment variables (recommended for CI/ephemeral environments)
  2. Local CLI config file (recommended for local workstation use)

Environment variables (highest precedence):

  • HETZNER_TOKEN for both Cloud and Storage APIs
  • HETZNER_CLOUD_TOKEN to override cloud auth token
  • HETZNER_STORAGE_TOKEN to override storage auth token
  • HETZNER_PROJECT to choose one configured local project profile for this session

Base URL safety:

  • Default API targets are locked to the official Hetzner HTTPS endpoints.
  • HETZNER_CLOUD_BASE_URL and HETZNER_STORAGE_BASE_URL are validated before any token is attached.
  • Custom base URLs are blocked by default to prevent credential exfiltration to non-Hetzner hosts.
  • For controlled test environments only, opt in explicitly with HETZNER_ALLOW_CUSTOM_BASE_URLS=true.

Local CLI config examples:

# set default token
hetzner-mcp auth set --token "your_token_here"

# auth set auto-probes what the provided key can do
# (cloud/storage + read/write capability hints)

# set per-domain overrides
hetzner-mcp auth set --cloud-token "cloud_token" --storage-token "storage_token"

# inspect effective token sources (env/file/unset)
hetzner-mcp auth show

# open full local config in your editor
hetzner-mcp config edit

Multi-project profile examples:

# create per-environment profiles
hetzner-mcp project add prod --description "Production Hetzner" --token "prod_token" --activate
hetzner-mcp project add staging --description "Staging Hetzner" --token "staging_token"

# project add also auto-detects capability hints for entered keys

# see which profile is active and what each one is for
hetzner-mcp project list

# switch active profile
hetzner-mcp project use staging

Capability probing notes:

  • auth set and project add automatically probe entered keys and print capability hints.
  • Report format includes per-domain read/write level plus probe status codes (for example cloud:read+write, storage:no-access).
  • Detection uses safe representative GET/POST checks and is best-effort guidance, not a formal permission matrix.

Config file location:

  • ~/.config/hetzner-mcp/config.json (macOS/Linux)
  • %APPDATA%\\hetzner-mcp\\config.json (Windows)
  • Override path with HETZNER_MCP_CONFIG_PATH

Optional runtime controls:

  • HETZNER_CLOUD_BASE_URL
  • HETZNER_STORAGE_BASE_URL
  • HETZNER_TIMEOUT_SECONDS
  • HETZNER_MAX_RETRIES
  • HETZNER_BACKOFF_BASE_SECONDS

Supported MCP Clients

Auto-configuration is included for:

Client Auto-config
Claude Desktop Yes
Claude Code Yes
Cursor Yes
Cline Yes
Windsurf Yes
OpenCode Yes

Run:

hetzner-mcp install

OpenCode integration note:

  • This installer writes OpenCode MCP config to the global OpenCode config file (opencode.jsonc) under the mcp key.
  • Legacy ~/.opencode/mcp.json is not used.

Manual Configuration

{
  "mcpServers": {
    "hetzner-mcp": {
      "command": "hetzner-mcp-server",
      "args": []
    }
  }
}

CLI Commands

Command Description
hetzner-mcp status Show effective runtime config + registry + client status
hetzner-mcp doctor [--json] Print detailed diagnostics
hetzner-mcp server run [--refresh-specs] Run stdio MCP server
hetzner-mcp update Refresh specs and re-apply client integration
hetzner-mcp client install Configure supported MCP clients
hetzner-mcp client status Show client config installation state
hetzner-mcp client repair Re-apply configuration entries
hetzner-mcp client uninstall Remove MCP config entries
hetzner-mcp auth set ... Configure API keys directly from CLI and auto-detect key capabilities
hetzner-mcp auth show Show token status and source
hetzner-mcp auth clear [--all] Clear stored token entries
hetzner-mcp project add/list/show/use/remove Manage multiple project credential profiles (with capability probing on add)
hetzner-mcp config show Show stored + effective config
hetzner-mcp config get/set/unset <key> Read/write persisted config keys
hetzner-mcp config edit Edit persisted config file in $EDITOR

Legacy aliases still work: install, repair, uninstall, diagnose.

Development

git clone https://github.com/devinoldenburg/hetzner-mcp.git
cd hetzner-mcp
python -m venv .venv
source .venv/bin/activate
pip install -e ".[dev]"

# Validate quality
ruff check .
mypy src
pytest

# Refresh specs and inspect counts
python scripts/sync_specs.py
python scripts/verify_operation_coverage.py

Security Notes

  • Never commit API tokens.
  • Tokens can be read from environment variables or persisted local config, but outbound API targets are validated before Authorization headers are sent.
  • Official Hetzner HTTPS base URLs are enforced by default; custom base URLs require explicit opt-in with HETZNER_ALLOW_CUSTOM_BASE_URLS=true.
  • Dynamic endpoint calls now validate path, query, and JSON body inputs against the loaded OpenAPI schema before making HTTP requests.
  • MCP tool responses redact common secret fields such as token, password, secret, and authorization to avoid leaking credentials into transcripts.
  • set_active_api_project now switches the active project for the current MCP session by default; use persist=true only when you intentionally want to update local config.
  • Server logs are routed to stderr to keep stdio JSON-RPC clean.
  • Network retries are limited and capped.

Troubleshooting

ModuleNotFoundError: hetzner_mcp in local scripts

  • Install editable package: pip install -e .

No operations listed in MCP client

  • Run hetzner-mcp status
  • Verify config file includes hetzner-mcp
  • Restart the client process after installation

Auth failures (401 unauthorized)

  • Ensure HETZNER_TOKEN or domain-specific token is exported in the client runtime environment

Rate limiting (429)

  • The client retries transient failures automatically; reduce request burst and retry later

License

MIT

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Model Context Protocol server bringing Hetzner to your AI agent

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